> ## Documentation Index
> Fetch the complete documentation index at: https://help.onlyx.ai/llms.txt
> Use this file to discover all available pages before exploring further.

> ## Agent Instructions
> You are reading OnlyX Help: the OnlyX Help Center and the OnlyX developer documentation. OnlyX is an AI chatting and CRM platform for OnlyFans agencies. Its AI chatter is called Hugo in the app.
> Pages at the site root (for example /inbox/..., /hugo/..., /billing/...) are Help Center articles for agency owners, admins, chatters and creators who use the app at app.onlyx.ai. Words in bold are the exact button, menu and label names the app shows; keep them exactly as written. When these pages do not answer a question, the person can email support at support@onlyx.ai.
> Pages under /developers are the developer documentation. REST API base URL: https://api.onlyx.ai/v1 (authenticate with `Authorization: Bearer <API key>`; keys start with onx_sk_ and are created in app.onlyx.ai under Settings > API & MCP). MCP server: https://mcp.onlyx.ai/mcp (OAuth, or a Bearer API key). In the API the AI chatter is `ai` on the wire. Money is integer US cents in fields ending in Cents; timestamps are UTC ISO-8601.
> Rules for assistants acting on a user's behalf: discover ids with list calls and never invent them; before any call that reaches a real fan or the live OnlyFans account (sending a message, releasing a chat to the AI, turning AI on for a chat, resolving a hand-off, turning review mode off, changing the welcome message, creating a tracking link) show the user the exact content and get explicit confirmation; send every POST with an Idempotency-Key and reuse it on retry; never resend a message whose delivery status is unconfirmed; never ask a creator for her OnlyFans password or codes - she signs in herself through a connect link and the OnlyX Login app.

# ChatGPT

> Connect OnlyX to ChatGPT as a Developer mode app with the URL https://mcp.onlyx.ai/mcp and OAuth sign-in.

ChatGPT connects to remote MCP servers through **Developer mode**. You create an app for OnlyX once, sign in with OAuth, and then turn it on in any chat. ChatGPT has no install link for MCP servers, so this takes about a minute of clicking.

**You need**:

* ChatGPT on the web with a **Plus, Pro, Business, Enterprise or Edu** plan (Developer mode is not available on Free). On Business, Enterprise and Edu, a workspace admin may first need to allow Developer mode or custom connectors for members.
* To be an **owner or admin** of your OnlyX workspace, to approve the connection.

The server URL is:

```text theme={"system"}
https://mcp.onlyx.ai/mcp
```

<Steps>
  <Step title="Turn on Developer mode">
    In ChatGPT open **Settings → Apps & Connectors → Advanced settings** and switch on **Developer mode**. (In some ChatGPT versions the switch is under **Settings → Security and login**.) Business, Enterprise and Edu admins control this under the workspace's permission settings.
  </Step>

  <Step title="Create the OnlyX app">
    Still in **Settings → Apps & Connectors**, click **Create** (in some versions **Create app** or **+**). Fill in:

    | Field | Value |
    | - | - |
    | Name | `OnlyX` |
    | Description | `My OnlyX agency: creators, inbox, fans, stats and AI settings` |
    | MCP server URL | `https://mcp.onlyx.ai/mcp` |
    | Authentication | **OAuth** |

    Leave client ID and secret empty: OnlyX registers ChatGPT automatically. Confirm that you trust the app and click **Create**.
  </Step>

  <Step title="Sign in to OnlyX">
    ChatGPT opens OnlyX's sign-in page. Sign in, choose the workspace, optionally limit ChatGPT to some creators, review the permissions, and click **Approve**. You are sent back to ChatGPT, and OnlyX appears under your apps (new Developer mode apps are listed as drafts).
  </Step>

  <Step title="Use it in a chat">
    In a new chat, open the **+** menu (or **Tools**), choose **Developer mode**, and turn on **OnlyX**. Then ask: *"Using OnlyX, which workspace am I connected to?"*
  </Step>
</Steps>

## Confirmations

ChatGPT asks you to confirm every action that is not read-only, and shows what it is about to send. Read it: for `send_message` that is the exact text, media ids and `priceCents` that will reach the fan. OnlyX's tools also tell ChatGPT to confirm fan-reaching actions with you in the chat first.

## API keys

ChatGPT connects with OAuth only; it cannot send a custom API key. To give ChatGPT less access, limit it to specific creators on the OnlyX consent screen, and revoke it any time in **Settings → API & MCP → Connected apps**. For read-only assistant access with a key, use a client that supports headers, such as [Claude Code](/developers/mcp/claude-code), [Cursor](/developers/mcp/cursor) or [VS Code](/developers/mcp/vscode).

## Troubleshooting

| Problem | Fix |
| - | - |
| No Developer mode switch | Your plan or workspace does not allow it. Check your plan, or ask your ChatGPT workspace admin. |
| "Error creating connector" | Check the URL is exactly `https://mcp.onlyx.ai/mcp` and that Authentication is set to OAuth. |
| The OnlyX sign-in says you cannot approve | Only OnlyX owners and admins can connect apps. |
| ChatGPT does not use OnlyX | Turn OnlyX on for this chat under Developer mode, and mention it in your request. |
| OnlyX stopped working after a while | The connection was revoked or your OnlyX role changed. Reconnect the app from its settings. |

## Next

* [Using OnlyX with Claude and other assistants](/developers/guides/using-with-claude): recipes that work the same in ChatGPT.
* [Tools](/developers/mcp/tools): what ChatGPT can do in OnlyX.